1. Field of the Invention
Various embodiments of the present invention relate to a buckle that includes a male member and a female member. Specifically, various embodiments of the invention relate to a buckle that is used to couple and separate ends of a string member or to couple and separate two string members.
2. Description of Related Art
A buckle is used for coupling and separating both ends of a string member or coupling and separating two string members. For example, a coupler that includes a male member and a cylindrical female member is disclosed in Japanese Patent No. 3790094. A pair of bowing portions project from the male member in the inserting direction. The bowing portion is provided with a projection. In the female member, a guiding receptacle is formed in a tapered-groove-shaped manner from an opening, into which the male member is inserted, toward an interior hollow portion along inner surfaces of an upper wall and a lower wall. A notch with which the projection of the male member engages is formed on the rear portion of the guiding receptacle.
When the projection of the male member is aligned with the upper and lower guiding receptacles of the female member and the male member is inserted to the female member, the projection proceeds along the tapered groove of the guiding receptacle, so that the bowing portion is elastically deformed inward. When the male member reaches a predetermined position, the projection slips into the notch to be engaged, so that the male member is engaged with the female member.
There are problems with the above coupler. For example, if the male member is obliquely inserted with respect to the direction of the guiding receptacle of the female member, the projection of the male member is not aligned with the upper and lower guiding receptacles of the female member, so that the male member is stuck halfway. As a consequence, the projection of the male member is required to be correctly aligned with the upper and lower guiding receptacles of the female member in order to have the male member properly inserted into the female member, thereby causing the inserting operation of the male member to be cumbersome.
A buckle disclosed in JP-A-2006-204911 is known as being capable of solving such problems. The buckle includes a male member and a female member. The male member is provided with a base, two locking arms that protrude from the base in the same direction as each other and have respectively a locking tab on a distal end thereof, and a V-shaped center portion that projects between the locking arms in the same direction as the locking arms to form a substantially triangular shape. The female member is provided with a cylindrical hollow body, where locking ends for engaging with the locking tabs of the male member are formed and a V-shaped groove for fitting with the V-shaped center portion of the male member is notched from an inserting opening toward the rear portion.
When the male member is inserted in the female member, while the two locking arms are elastically deformed inward for insertion, the V-shaped center portion of the male member is inserted into the V-shaped groove of the female member. At this time, if the inserting direction of the male member is oblique with respect to the cylindrical axis of the female member, the V-shaped center portion of the male member is abutted to the groove face of the V-shaped groove of the female member and inserted along the groove face of the V-shaped groove. Thus, the posture of the male member is corrected. In other words, the posture of the male member is corrected so that the inserting direction of the male member is formed parallel with respect to the cylindrical axis of the female member. Accordingly, even when the male member is inserted in an inserting direction oblique with respect to the cylindrical axis of the female member, the male member can be inserted in the female member.
In the buckle disclosed in JP-A-2006-204911, the inserting posture of the male member is corrected by the V-shaped center portion disposed at the widthwise center of the male member and the V-shaped groove disposed at the widthwise center of the female member. Accordingly, the posture-correcting function does not work until the male member is inserted into the female member to a certain extent since the V-shaped center portion of the male member is not yet abutted to the groove face of the V-shaped groove of the female member.
Therefore, if the inserting direction of the male member is significantly oblique with respect to the cylindrical axis of the female member, it is possible that the posture-correction does not function, causing the male member to be stuck halfway. In this case, the male member has to be disengaged from the female member to be inserted again. To avoid this, the inserting operation needs to be conducted carefully.